Sonic nebulizer

ABSTRACT

A sonic nebulizer having an electronic powered piezo-electric crystal to produce mechanical vibrations which are transmitted through a coupling fluid and focused on a second fluid contained in a chamber having a tangentially directed pressurized air inlet and a central opening whereby the nebulized second fluid is entrained by the vortex air flow generated in the chamber and the resulting fluid mixture carried through the outlet. The coupling fluid, electric power oscillator, piezo-electric crystal and associated control apparatus are contained by a portable casing which presents a compact, lightweight and rugged unit particularly adapted for short or long term use in supplying medicated air or oxygen to a patient undergoing medical care. The chamber containing the nebulized second fluid is made of an inexpensive, transparent material which is quickly and easily mounted to the casing and attached to inlet and outlet hoses. The inlet and outlet hoses, like the chamber, may be made from inexpensive material and together with the chamber constitute a disposable portion to avoid contamination between patients.

United States Patent Millman 51 Sept. 12, 1972 [54] SONIC NEBULIZER [72]Inventor: William V. Milhnan, Davenport,

Iowa

[73] Assignee: The Bendix Corporation [22] Filed: Oct. 29, 1970 [21]Appl. No.: 85,069

[52] US. Cl. ..128/194, 239/102, 310/83 [51] Int. Cl. ..A6lh l/00, A6lm15/00 [58] Field of Search ..l28/194, 193, 188, 173, 172,

128/186, 191, DIG. 2; 239/338; 310/8.1, 8.7,

3/1971 Mahon ..l28/194 X Primary Examiner-Richard A. Gaudet AssistantExaminer-G. F. Dunne Attorney-Gordon H. Chenez and Plante, l-lartz,

Smith & Thompson [57] ABSTRACT A sonic nebulizer having an electronicpowered piezoelectric crystal to produce mechanical vibrations which aretransmitted through a coupling fluid and focused on a second fluidcontained in a chamber having a tangentially directed pressurized airinlet and a central opening whereby the nebulized second fluid isentrained by the vortex air flow generated in the chamber and theresulting fluid mixture carried through the outlet. The coupling fluid,electric power oscillator, piezo-electric crystal and associated controlapparatus are contained by a portable casing which presents a compact,lightweight and rugged unit particularly adapted for short or long termuse in supplying medicated air or oxygen to a patient undergoing medicalcare. The chamber containing the nebulized second fluid is made of aninexpensive, transparent material which is quickly and easily mounted tothe casing and attached to inlet and outlet hoses. The inlet and outlethoses, like the chamber, may be made from inexpensive material andtogether with the chamber constitute a disposable portion to avoidcontamination between patients.

7Claims,5DrawingFigures PATENIEBSEP I2 m2 SHEET 1 OF 2 BACKGROUND OF THEINVENTION to permit sterilization before use on another patient.

Other undesirable characteristics include disassembly problems involvedin replacing critical parts subject to deterioration and replacementunder normal usage.

In particular, the design of prior art nebulizers precludes accuratecontrol over the quantity of medicament nebulized over a given period oftime so that'a specified medicant-air and/or oxygen mixture can bemaintained to a patient over a short or long time period.

SUMMARY OF THE INVENTION It is an object of the present invention toprovide a sonic nebulizer characterized by structural simplicity,compactness and lightweight which renders the same readily portable foruse at substantially any desired location in a hospital or home.

It is an important object of the present invention to provide a sonicnebulizer characterized by reliability of operation and ruggedness evenunder continuous usage.

It is another object of thepresent invention to provide a sonicnebulizer which is relatively inexpensive to manufacture and operate andcapable of providing a wide range of aerosol output with or withoutmedicaments. It is another object of the present invention to provide asonic nebulizer which is easy to clean and sterilize and wherein theportions thereof normally exposed to contamination by a patienttemporarily using the same are disposable to prevent cross contaminationto a subsequent patient using the same.

It is another object of the present invention to provide a sonicnebulizer characterized by a wide range of aerosol output flow therebyadapting the same for medical use with a face mask or tent.

It is still another object of the present invention to provide aninexpensive, disposable nebulizer chamber including medicant cup whichis rugged, efficient and easily attached to or removed from associatednebulizer apparatus.

Other objects and advantages will be apparent from the followingdescription taken with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 represents a sectional view ofa sonic nebulizer embodying the present invention;

FIG. 2 represents an end view of the apparatus of FIG. 1;

FIG. 3 represents a sectional view of a piezo-electric transducerassembly;

FIG. 4 represents a sectional view taken on line 4-4 of FIG. 1.

FIG. 5 represents a portion of FIG. 1 modified to provide greater outputflow for tent use.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, FIG.1 in particular, numeral 20 designates a generally rectangular shaped,multi-section casing having an upper section 22 defining a fluidreservoir and a lower section 24 housing various control elements aswill be described. The upper section 22 rests upon the lower section 24and is readily separable therefrom. Preferably, the casing 20 isconstructed from any suitable plastic material which may be easily andquickly formed to the required shape and having desirablecharacteristics including low cost, strength as well as being impactresistant, lightweight, electrically non-conductive and corrosionresistant.

The lower section 24 is supported by a plurality of spaced-apart legsgenerally indicated by 26 suitably secured thereto. An air inlet 28 inlower section 24 is provided with an air filter element 30 securedtherein by integral flexible clips 32 which engage casing 20. A floor orplatform 34 is positioned on a plurality of spaced apart supports 36integral with casing 20 by fasteners 35, only one being shown. Thesupports 36 hold the platform 34 a uniform distance from the base 38 toform a passageway 33 therebetween.

A control panel 40 fixedly secured to platform 34 by suitable fasteningmeans such as screws 41 is held in spaced-apart relationship to an airoutlet 42 in lower section 24 through which pressurized air isdischarged from the interior of lower section 24. An air outlet openingis defined by a fitting 44 fixedly secured to control panel 40 by a locknut 46 threadedly engaged therewith. Various control members including apower regulator 48 having an adjustable control knob 50 movable betweenlow and high power settings, an air control push to operate controlmember 52, a fuse block 54, an ON-OFF push button switch 56 and a timer58 for indicating elapsed time of operation are suitably connected topanel 40 for control purposes.

The air inlet of fitting 44 is isolated from air flowing to air outletopening 42 by partition means including a wall 60 extending at an angleto panel 40 and provided with suitable integral end wall portions 62only one of which is shown. A truncated plug or valve member 59 fixed toa plate 61 is adapted to move relative to the inlet of fitting 44 tovary the effective flow area of fitting 44. The plate 61 is secured to ashaft 63 suitably mounted for rotation and actuated by a link 65connected to air control member 52. The wall 60 is suitably flanged topermit opposite edge portions thereof to be fixedly secured to controlpanel 40 and platform 34 by suitable fastening means such as screws Apower control unit generally indicated by 66 is connected to a source ofelectric power via insulated power cord 68. The power control unit 66 isprovided with suitable flange members 70 fixedly secured to platform 34by any suitable means such as rivets 72 to thereby provide support forpower control unit 66. The power control unit 66 including internalelectronic circuitry thereof is fully described as well as claimed incopending application Ser. No. 45,163 filed June 10,

1970 now US. Pat. No. 3,648,188 in the name of H. Ratcliff, owned by thecommon assignee of this application and incorporated by reference. Ingeneral, the power control unit 66 is adapted to receive an electricinput via lead 68 and control the same to a desired oscillating electricoutput of predetermined frequency and amplitude. To that end, the powerregulator 48 is electrically connected to power control unit 66 suchthat any desired electrical power output within the established rangemay be selected by rotating control knob 50 to the proper position.

A housing 74 is fixedly secured to platform 34 by suitable fasteningmeans including a plurality of nut and bolt. combinations 76. Thehousing 74 houses a conventional air blower 78 rotatably supportedtherein and driven by an electric motor 80 suitably connected to lead68. The housing 74 is provided with an air inlet 82 exposed to filteredair from air inlet 28 and an air outlet 84 for discharging pressurizedair to an air channelv partially defined by platform 34 and base 38between which the air flows to an opening 86 in platform 34 thence toair outlet fitting 44. A fan 87 driven by shaft 77 of electric motor 80receives air from air inlet 28 and urges the same through lower section24 to air outlet 42 to thereby provide cooling air flow which passesover power control unit 66 to dissipate heat generated thereby. A shroud88 suitably mounted around fan 87 confines the incoming air to passagethrough fan 87.

The lower section 24 isprovided with a dished upper wall portion 90provided with an opening 92 having a flanged edge 94. A cup-shapedreceptacle 96 flanged to mate with flanged edge 94 is fixedly securedthereto by any suitable means such as an adhesive or the like. Anopening 98in the base of receptacle 96 is provided for a purpose to bedescribed.

- The upper section 22 is contoured to mate with dished upper wallportion 90 and has a flanged opening 100-formed therein. A sleeve 102having a shoulder 104 formed in the upper end thereof is received byflanged opening 100 to which the sleeve 102- is fixedly secured by anysuitable means such as an adhesive providing a fluid seal. The innerwall of sleeve 102 is threaded as at 106 and adapted to threadedlyreceive an energy transducer or piezo-electric crystal assemblygenerally indicated by 108. The upper section 22 is provided with acover 110 having a channeled edge section 112 adapted to engage aresilient seal 113 secured to the wall of upper section 22 to therebyhold cover 110 in position securely. An opening 114 in cover 110 isadapted to receive a standard U.S.P. bottle, not shown, for supplyingfluid to the reservoir defined by upper section 22. A cap 116 suitablysecured in opening 114 serves to plug the same in the event aconventional U.S.P. bottle is not used as will be described. An opening118 in cover 110 is aligned with a sleeve 120 having a radiallyextending wall 123 fixedly secured to cover 110 by any suitable meanssuch as adhesive or the like. The sleeve 120 is aligned with sleeve 102containing the piezo-electric crystal assembly 108 and extends below thelevel of fluid in upper section 22.

A nebulizing chamber is defined by a container 122 preferably circularin form and molded from any suitable relatively inexpensivethermoplastic material. The

container 122 is provided with an integral tubular extension 124defining an air inlet located to direct pressurized air tangentiallyinto container 122 as indicated in FIG. 4. An integral two diametertubular extension 126 centrally located in the top of container 122provides an air outlet for container 122. The tubular extensions 124 and126 are provided with corrugations 128 adapted to engage respectivemating coupling members 130 and 132 suitably fixed to one end offlexible inlet and outlet hoses 134 and 136, respectively. The oppositeend of inlet hose 134 is provided with a coupling 138 suitably fixedthereto which is adapted to engage a corrugated portion 128 of fitting44. The opposite end of outlet hose 136 is adapted to be removablyattached to a conventional breathing mask, not shown. The container 122has an integral outwardly extending annular rib 140 and an adjacentintegral annular recess 142 molded therein and located at approximatelythe midportion of container 122. An annular recess 144 is defined by anoutwardly extending annular rib 146 formed in a reduced diameter whichtransitions into a substantially flat base portion 148 of container 122.The base portion 148 and, in particular, the portion thereof exposed tothe piezo-electric crystal assembly 108 is carefully controlled duringmolding thereof for a purpose to be explained. It will be noted that thecontainer 122 is received by sleeve 120 and securely held in positiontherein by the edge portion of opening 118 which snap fits into recess142.

Referring to the two diameter extensions 126, the smaller diameterportion 150 thereof is adapted for connection to hose 136 which, inturn, connects to a breathing mask. However, the above-describedapparatus may be readily modified for tent use in which case the airflow volume as well as the volume of nebulized fluid must be increasedsignificantly over that required for mask use. To that end, the baseportion of container 122 is adapted tobe cut off at the annular recess144 to expose the interior of container 122 to the liquid reservoir inupper section 22.

The larger diameter portion 152 of extension 126 is provided with anannular recess 154 defined by spacedapart annular ribs 156 and 158. Theextension 126 may be cut off at recess 154 thereby providing an enlargeddiameter outlet for the container 122 as indicated in FIG. 5. A sleeve160 attached to one end of a corresponding relative large diameterflexible hose 162 leading from a tent, not shown, is slidably receivedby the larger diameter portion 152 and extends axially through container122 to approximately the open end thereof. A shoulder 162 formed onsleeve 160 engages the rib 158 to thereby locate the axial position ofsleeve 160.

The container 122 may be provided with an integral nipple 163 which issnipped off in the event that oxygen enrichment is desired. To that end,a source of pressurized oxygen, not shown, is provided with an outlethose adapted to be secured to the inlet opening defined by the snippedoff nipple 163.

Referring to FIG. 3, the piezo-electric crystal assembly 108 is shown insection. An annular housing 164 preferably formed from an electricallynon-conductive material is provided with a threaded section 166 and areduced diameter end portion defining an opening 168 and shoulder 170. Aflat piezo-electric 12) thick is suitably bonded to the disc 172 bymeans 5 of an epoxy to thereby establish a well-known resonant system.In general, the stainless steel disc 174 functions to load thepiezo-electric disc 172 to prevent self destruction thereof when a highelectrical input is applied thereto and further functions to storeenergy thereby increasing the mechanical Q operation as will berecognized by those persons skilled in the art. An electricallyconductive slug or disc 176 bears against the disc 172 and has aterminal 178 fixedly secured thereto which receives a wire lead 180. Theslug or disc 176 is securely mounted on an annular flange 181 of aconventional thermostat assembly 182 by means of an adhesive 184 or thelike. The thermostat assembly 182 is provided with terminals 186 and188, each of which extend through an associated opening of a pluralityof openings 190 in insulating disc 192 of electrically nonconductivematerial.

A cap 194 is provided with an annular extension 196 which extends intothe interior of housing 164 into engagement with one end of a sleeve 198slidably engaged with the interior wall of housing 164. The opposite endof sleeve 198 bears against piezo-electric disc 172. An 0 ring seal 200trapped between shoulder 170 and disc 174 is compressed therebyestablishing a fluid seal sulate the thermostat assembly 182, slug 176and associated mechanism fromv sleeve 198. A compression spring 204interposed between cap 194 and insulating disc 192 loads the thermostatassembly 182- and thus slug 176 to thereby maintain positive electricalcontact between slug 176 and piezo-electric disc 172. A wire 206connects terminal 188 with slug 176.

A conventional RF connector plug 208 threadedly engaged with cap 194 issuitably connected via a wire 210 to terminal 186 of thermostat assembly182. Current flow passes through thermostat assembly 182 to terminal 188then via wire 206, slug 176, piezo-electric It will be noted that thesleeve 198 and cap 194 are necessarily made from electrically conductivematerial. Also, it will be recognized that the thermostat assembly 182and piezo-electric disc 172 are in series flow relationship such thatcurrent flow through the disc 172 is vided in power control unit 66.

Referring to the fitting 44, reverse air flow therethrough is obstructedby a flexible wall or flapper 210 suitably enclosed as by member 212 atits center to fitting 44. The flexible wall 210 allows pressurized airto pass therethrough to hose 134. However, in the event of a patientcoughing or the like in his mask, the resulting back flow throughcontainer 122 and thus hose 134 is prevented from entering fitting 44 byclosing of flexible wall 210 thereby eliminating contamination of thestructure upstream from the fitting 44.

OPERATION OF THE PREFERRED EMBODIMENT Applicants nebulizer apparatus maybe easily and quickly set up for operation in any suitable locationrelative to a patient requiring aerosol therapy. To that end, the uppersection 22 is positioned on lower section 24 with the connector plug 208engaged with the power control unit 66. The therapist may then fill theupper section 22 defining the liquid reservoir to the indicated level byremoving cap 116 and inserting standard U.S.P. bottles containing wateror saline solution in opening 114. When the liquid in upper section 22reaches the desired level, the neck of U.S.P. bottle is immersed therebyblocking air flow into the bottle and controlling the liquid levelaccordingly.

The container 122 or nebulizing chamber is inserted into opening 118 andsecured in position therein by cover which snaps into recess 142. Thedesired quantity of a liquid medicant to be nebulized is poured intocontainer 122 through extension 126. The coupling members and 138 onopposite ends of flexible hose 134 are snapped in position oncorrugations 128 of extension 124 and fitting 44, respectively. Thecoupling member 132 on one end of flexible hose 136 is snapped inposition on the corrugations 128 of the smaller diameter portion ofextension 136.

The power cord 68 is plugged into a suitable electrical receptacle andthe push button switch 56 actuated to the ON position. The power controlknob 50 is adjusted to the desired power setting and the air control 52set to position valve member 59 which, in turn, establishes theeffective flow area of fitting 44 and thus air volume to the container122.

The setting of power control knob 50 determines the electrical outputimpressed on piezo-electric disc 172 and thus resulting sonic energygenerated thereby which sonic energy is directed through opening 168causing the liquid reservoir or coupling liquid in upper section 22 topile up into a fountain shaped wave. The created sonic energy will beconcentrated at a flat peak of the fountain shaped wave causing the tipof the wave disc 172, sleeve 198 and cap, in that order, to plug 208. 50

to be dispersed as droplets into the surrounding space. However the baseportion 148 of container 122 is placed in the fountain shaped wave. Thebase portion is carefully molded of a thickness which will not affectthe transmission of sonic energy from crystal assembly 108. A thicknessfor the base 148 equal to one quarter wave length or less of theacoustic wave imposed on the base portion 148 will be acousticallytransparent to the sonic energy passing therethrough permitting theformation of the fountain shaped wave in the medicament. The resultingagitation of themedicament causes the same to be dispersed into a mistdefined by small particles of the medicant.

The pressurized air introduced into the container 122 via inlet hose 134is directed tangentially into container 122 and follows a vortex path inpassing to the outlet extension 126. The nebulized medicament incontainer 122 is entrained by the air flow which causes the largerparticles of medicament to move radially outwardly in container 122 inresponse to the centrifugal force imposed on the particles by virtue ofthe vortex action such that only thoroughly dispersed relatively smallparticles of medicament are carried by the air flow through outletextension 126 to the outlet hose 136 for subsequent inhalation by thepatient. Treatment is discontinued when the medicament in container 122is used up following which the power unit 66 is shut off whereupon upperand lower sections 22 and 24 may be transferred to another location foruse by a second patient if desired. The inlet and outlet hoses 134 and136 are disconnected from fitting 44 and the inhalation mask,respectively, and the container 122 detached from cover 110, all ofwhich may be discarded and replaced by an unused container 122 andunused inlet and outlet hoses 134 and 136 thereby preventing crosscontamination between patients. The sections 22 and 24 including theliquid reservoir are not contaminated and may be used repeatedly sincethe sections are not exposed to a patient.

The nipple 163 is located adjacent air inlet extension 124 such thatoxygen introduced therethrough to container 122 tends to be entrained bythe air flow through extension 124.

Applicants nebulizing apparatus may be set up for tent therapy quicklyand conveniently. To that end, the base portion 148 v of container 122is removed by cutting along recess 144 and the smaller diameter portion150 of extension 126 removed by cutting along recess 154. The sleeve 160may then be inserted into larger diameter portion 154 of extension 126as shown in FIG. 5. The sonic energy derived from the piezoelectriccrystal assembly 108 is imposed on the liquid reservoir in upper section22 creating a fountain-like mass of liquid particles adjacent the lowerend of sleeve 160 which particles are swept along by the vortex air fiowthrough container 122, which exits through sleeve 160 and hosev 162attached thereto to the tent. In this manner, the large liquid reservoirsupplemented by standard U.S.P. bottles attached to cover 110 andreplaced as required permits hours of continuous fog in suitable volumefor tent therapy;

The upper and lower sections 22 and 24 may be readily cleaned as desiredby removing the cover 110 and unplugging the upper section 22 from thelower section 24 which cover 110 and section 22 may be easily andthoroughly washed and sterilized since there are no small, inaccessibleplaces to contend with therein.

With the upper section 22 unplugged from lower section 24, thepiezo-electric crystal assembly 108 may be removed therefrom simply andquickly by unscrewing the same from sleeve 102 and screwing in areplacement crystal assembly if required.

l claim:

1. A portable sonic nebulizing apparatus for use in treating anindividual with a respiratory problem requiring conditioned air, saidapparatus comprising:

a first housing having an inlet port, a first outlet, a second outletand a third outlet, said first housing having a flange around said firstoutlet, said housing retaining an electrical power control adjacent saidfirst outlet;

fan means adjacent the inlet port in said first housing for moving airalong a first path to said second outlet and a second path to said thirdoutlet, said air moving in said first path removing thermal energy fromsaid electrical power control;

a filter member located in said inlet port to remove impurities from theair received by said fan means, a second housing positioned on saidfirst housing having a first opening, a second opening and a thirdopening, said second and third openings being in axial alignment withsaid first outlet port of the first housing, said second opening havinga sleeve extending inwardly toward said third opening a predetermineddistance;

sonic energy means sealed in said third opening of said second housinghaving an extension passing through said first outlet in the firsthousing connecting said sonic energy means with said electrical powercontrol;

cylindrical container means resiliently retained in said second openingand sleeve of the second housing having a substantially fiat base whichis in axial alignment with said sonic energy means, said fiat baseextending into the sleeve a predetermined distance from said secondopening, said container means retaining a fluid medicament which aids inrelieving said respiratory problem, said container meanshaving atangential entrance passage and an axial exit passage, said tangentialentrance passage being connected to said third outlet in the firsthousing for delivering all of the filtered air from said fan means insaid second path, said tangential entrance causing the filtered air tofollow a vortex flow path in said cylindrical container, a couplingfiuid located in said second housing; and

control means connected to said electrical power control for activatingthe sonic energy means for creating a fountain shaped energy wave insaid coupling fiuid, said base of the cylindrical container means beinglocated in said fountain shaped energy wave, said fountain shaped energywave passing through said base unobstructed causing the medicament to bedispersed as droplets in said vortex flow path of the filtered air, saiddroplets being suspended in said air, said exit passage being connectedto the patient for delivering the medicament droplets in the filteredair.

2. The apparatus as recited in claim 1 wherein the control means furtherincludes:

fiow control means in said second path adjacent the third outlet in thefirst housing for regulating the quantity of filtered air deliveringsaid tangential entrance into the cylindrical container means toselectively establish said vortex flow path corresponding to the need ofthe individual user.

operation of the sonic energy means when the sensed thermal level insaid sonic energy means corresponds to a predetermined value.

container means. 7. The apparatus as recited in claim 6 wherein saidcontainer means further includes: i

an additive entrance downstream from said tangential entrance passageconnected to a source of oxygen to further condition the filtered air byenriching the oxygen content therein.

* II! k

1. A portable sonic nebulizing apparatus for use in treating anindividual with a respiratory problem requiring conditioned air, saidapparatus comprising: a first housing having an inlet port, a firstoutlet, a second outlet and a third outlet, said first housing having aflange around said first outlet, said housing retaining an electricalpower control adjacent said first outlet; fan means adjacent the inletport in said first housing for moving air along a first path to saidsecond outlet and a second path to said third outlet, said air moving insaid first path removing thermal energy from said electrical powercontrol; a filter member located in said inlet port to remove impuritiesfrom the air received by said fan means, a second housing positioned onsaid first housing having a first opening, a second opening and a thirdopening, said second and third openings being in axial alignment withsaid first outlet port of the first housing, said second opening havinga sleeve extending inwardly toward said third opening a predetermineddistance; sonic energy means sealed in said third opening of said secondhousing having an extension passing through said first outlet in thefirst housing connecting said sonic energy means with said electricalpower control; cylindrical container means resiliently retained in saidsecond opening and sleeve of the second housing having a substantiallyflat base which is in axial alignment with said sonic energy means, saidflat base extending into the sleeve a predetermined distance from saidsecond opening, said container means retaining a fluid medicament whichaids in relieving said respiratory problem, said container means havinga tangential entrance passage and an axial exit passage, said tangentialentrance passage being connected to said third outlet in the firsthousing for delivering all of the filtered air from said fan means insaid second path, said tangential entrance causing the filtered air tofollow a vortex flow path in said cylindrical container, a couplingfluid located in said second housing; and control means connected tosaid electrical power control for activating the sonic energy means forcreating a fountain shaped energy wave in said coupling fluid, said baseof the cylindrical container means being located in said fountain shapedenergy wave, said fountain shaped energy wave passing through said baseunobstructed causing the medicament to be dispersed as droplets in saidvortex flow path of the filtered air, said droplets being suspended insaid air, said exit passage being connected to the patient fordelivering the medicament droplets in the filtered air.
 2. The apparatusas recited in claim 1 wherein the control means further includes: flowcontrol means in said second path adjacent the third outlet in the firsthousing for regulating the quantity of filtered air delivering saidtangential entrance into the cylindrical container means to selectivelyestablish said vortex flow path corresponding to the need of theindividual user.
 3. The apparatus as recited in claim 2 wherein thethickness of the base of said fluid container is less than h/4 wavelength of the vibrating frequency of the sonic energy means to preventdestruction of the cylindrical container means by thermal energy.
 4. Theapparatus as recited in claim 3 wherein the control means furtherincludes: temperature responsive means for interrupting the operation ofthe sonic energy means when the sensed thermal level in said sonicenergy means corresponds to a predetermined value.
 5. The apparatus asrecited in claim 2 wherein said third opening in said second housing andthe sonic energY means are threadedly engaged to permit easy removalthereof from the sonic energy means.
 6. The apparatus as recited inclaim 5 further including: flow restricting means adjacent the thirdoutlet in the second flow path for preventing backflow from thecontainer means.
 7. The apparatus as recited in claim 6 wherein saidcontainer means further includes: an additive entrance downstream fromsaid tangential entrance passage connected to a source of oxygen tofurther condition the filtered air by enriching the oxygen contenttherein.